A serving of most sweetened breakfast cereals, according to the Nutrition Labeling and Education Act, is 30 grams. That comes out to about three-quarters of a cup, as listed on the label.

Kashi Go Its 11 grams of protein and 13 grams of fiber is a go-to for a balanced breakfast. Adding fruit and seeds can quickly bring this cereal into the 25-30 gram protein range. Berry Berry Kix ...

Cereals are among the highest source of fiber for Americans. Mohr recommends choosing a cereal with at least three grams of fiber per serving, though many cereal types offer much more fiber than that.